SOURCE

<div class="item-cell">
  <div class="hd">姓名</div>
  <div class="bd"><input type="text" class="inp"/></div>
</div>

<div class="item-cell">
  <div class="hd">姓名</div>
  <div class="bd"><input type="text" class="inp"/></div>
</div>

.item-cell{ 
    position: relative;
    display: -webkit-box;
    display: -webkit-flex;
    display: flex;
    -webkit-box-align: center;
    -webkit-align-items: center;
    align-items: center;
    padding:5px;
}
.item-cell .hd{ width:3em;}
.item-cell .bd {  
    -webkit-box-flex: 1;
    -webkit-flex: 1;
    flex: 1;
}
.item-cell .bd .inp{ 
  width:100%; 
  border:1px solid #e5e5e5; 
  line-height: 1.47em;
}